The Earth Exerts the Necessary Centripetal Force on an Orbiting

Multiple Choice

The Earth exerts the necessary centripetal force on an orbiting satellite to keep it moving in a circle at constant speed. Which one of the following statements best explains why the speed of the satellite does not change although there is a net force exerted on it?

A) The satellite is in equilibrium.
B) The acceleration of the satellite is zero m/s².
C) The centripetal force has magnitude mv²/r.
D) The centripetal force is canceled by the reaction force.
E) The centripetal force is always perpendicular to the velocity.